JP5532077B2 - Liquid ejection device - Google Patents

Description

  The present invention relates to a liquid ejection device that ejects liquid droplets from a plurality of ejection ports.

  Inkjet printers are known in which the thickened ink in the nozzles of a line-type inkjet head is discharged to a purge area defined on a belt that conveys paper, and a belt cleaner cleans the purge area from which the ink has been discharged. (For example, refer to Patent Document 1).

JP 2005-119284 A

  In order to reduce the bleeding of dots formed on the paper or to improve the color development of the dots by discharging the ink onto the paper, the pigment component of the ink is aggregated or deposited at the locations where the dots are formed. An ink jet printer having a processing liquid head that discharges a processing liquid is known. According to the above-described technique, the ink discharged from the inkjet head and the processing liquid discharged from the processing liquid head may be mixed with each other on the conveying surface of the conveying belt or the belt cleaner to generate aggregates or precipitates. is there. As a result, the generated aggregates or precipitates adhere to the conveyance surface of the conveyance belt and the belt cleaner, and the paper is soiled, and the conveyance capability of the paper and the cleaning capability of the cleaning mechanism such as the belt cleaner are deteriorated. is there.

  An object of the present invention is to provide a liquid ejection apparatus capable of preventing a decrease in recording medium conveyance capability and conveyance surface cleaning capability.

The liquid ejection apparatus of the present invention includes a conveyance mechanism that conveys a recording medium by moving an endless conveyance surface, and a first ejection port that ejects a first liquid that forms an image on the recording medium. One liquid head and a second liquid which is provided at a position different from the first liquid head with respect to the conveyance direction of the recording medium and which acts on the first liquid to agglomerate or deposit components in the first liquid. A second liquid head in which a second discharge port is formed, first discharge means for discharging the first liquid from the first discharge port, and second discharge for discharging the second liquid from the second discharge port. Means, a first cleaning mechanism having a first removal member for removing the first liquid adhering to the transport surface by abutting on the transport surface, and contacting the transport surface by contacting the transport surface. The second attached And includes a second cleaning mechanism having a second removing member for removing the body, the conveying mechanism, and control means for controlling said first and said second discharge means and the first and the second cleaning mechanism. The first liquid head is disposed downstream of the second liquid head in the transport direction, and the first removal member is disposed downstream of the first liquid head in the transport direction; The second removal member is disposed between the first liquid head and the second liquid head in the transport direction. The control unit controls the transport mechanism and the first discharge unit to discharge the first liquid onto the transport surface, and then discharges the first liquid from the first discharge port to the transport surface. The transport mechanism and the first cleaning mechanism are such that the first liquid adhering to the surface is removed by the first removal member without reaching the position facing the second removal member and the second discharge port. controls, then, the second liquid after controlling the second discharge means to the conveying mechanism so as to discharge onto the transport surface, wherein by being discharged to the conveying surface from the second discharge port The transport mechanism and the second cleaning are performed such that the second liquid attached to the transport surface is removed by the second removal member without reaching the position facing the first removal member and the first discharge port. Control the mechanism.

According to the present invention, since the first liquid and the second liquid discharged to the transport surface do not mix with each other, aggregates and precipitates are generated and fixed on the transport surface and the first and second cleaning mechanisms. Can be suppressed. As a result, it is possible to prevent a decrease in the conveyance capability of the recording medium related to the conveyance mechanism and the cleaning capability of the conveyance surface related to the first and second cleaning mechanisms. In addition, the liquid discharged from the first discharge port can be removed without passing the position facing the second discharge port, and the liquid discharged from the second discharge port is positioned facing the first discharge port. Can be removed without passing through. Thereby, it is possible to prevent the first liquid and the second liquid discharged on the transport surface from adhering to the second discharge port and the first discharge port, respectively. In addition, it is not necessary to switch the transport direction of the endless transport surface between when the first liquid is removed by the first removal member and when the second liquid is removed by the second removal member. By performing the removal of the second liquid in a continuous operation, the maintenance operation can be completed quickly.

  In the present invention, the first cleaning mechanism further includes a first storage mechanism for storing the first liquid removed by the first removal member, and the second cleaning mechanism is formed by the second removal member. A second storage mechanism for storing the removed second liquid; a flow path for guiding the first liquid removed by the first removal member to the first storage mechanism; and a second removal member. It is preferable that the flow paths for guiding the removed second liquid to the second storage mechanism are different from each other. According to this, since the first liquid and the second liquid discharged to the transport surface are removed and stored without being mixed with each other, agglomerates and precipitates are prevented from sticking in the recovery path of the discharged liquid. can do.

  At this time, at least one of the first and second removing members may remove the first or second liquid adhering to the transport surface in a planar region facing upward on the transport surface. According to this, it can suppress that each discharged liquid leaks from a conveyance surface.

Alternatively , at least one of the first removal members may remove the first liquid adhering to the transport surface on a curved surface that curves downward from above in the transport surface. According to this, since the 1st liquid adhering to a conveyance surface is removed in the state where it rose, each discharged | emitted liquid can be removed efficiently.

  In the present invention, the control means discharges the liquid from the first discharge port to the first discharge region on the transport surface, and differs from the first discharge region in the transport direction on the transport surface. It is preferable to control the transport mechanism, the first discharge unit, and the second discharge unit so that the liquid from the second discharge port is discharged to the discharge region. According to this, it is possible to further prevent the agglomerates and precipitates from sticking on the conveying surface.

According to the present invention, since the first liquid and the second liquid discharged to the conveyance surface do not mix with each other, aggregates and precipitates are generated on the conveyance surface and the first and second cleaning mechanisms. Can be suppressed. As a result, it is possible to prevent a decrease in the conveyance capability of the recording medium related to the conveyance mechanism and the cleaning capability of the conveyance surface related to the first and second cleaning mechanisms. In addition, the liquid discharged from the first discharge port can be removed without passing the position facing the second discharge port, and the liquid discharged from the second discharge port is positioned facing the first discharge port. Can be removed without passing through. Thereby, it is possible to prevent the first liquid and the second liquid discharged on the transport surface from adhering to the second discharge port and the first discharge port, respectively. In addition, it is not necessary to switch the transport direction of the endless transport surface between when the first liquid is removed by the first removal member and when the second liquid is removed by the second removal member. By performing the removal of the second liquid in a continuous operation, the maintenance operation can be completed quickly.

1 is a schematic side view of an inkjet printer according to a first embodiment of the present invention. It is a top view which concerns on the head main body of the inkjet head shown in FIG. It is an enlarged view of the area | region enclosed with the dashed-dotted line shown in FIG. It is a functional block diagram of the control apparatus shown in FIG. It is a figure for demonstrating the maintenance operation | movement in the inkjet printer shown in FIG. It is a figure for demonstrating the maintenance operation | movement in the inkjet printer shown in FIG. It is a schematic side view of the inkjet printer by 2nd Embodiment of this invention. It is a schematic side view of the inkjet printer by 3rd Embodiment of this invention. It is a schematic plan view of the inkjet printer by 4th Embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
As shown in FIG. 1, the inkjet printer 101 includes a transport unit 20 that transports the paper P from the right to the left in FIG. 1, and black (K) and cyan (cyan) on the paper P transported by the transport unit 20. C) Four inkjet heads 1 that respectively eject magenta (M) and yellow (Y) ink droplets, and the pigment components of each ink disposed upstream in the transport direction of the four inkjet heads 1 A precoat head 2 that ejects droplets of a precoat liquid (Pre) to be deposited, an ink pump 32 (see FIG. 4), a precoat pump 33 (see FIG. 4), a head lifting mechanism 34 (see FIG. 4), and an ink A cleaner 37, a precoat cleaner 38, and a control device 16 that controls the entire inkjet printer 101 are provided. In the present embodiment, the sub-scanning direction is a direction parallel to the transport direction when the paper P is transported by the transport unit 20, and the main scanning direction is a direction orthogonal to the sub-scanning direction and along the horizontal plane. Direction. In addition, a precoat liquid for aggregating pigment pigments is used for pigment ink, and a precoat liquid for depositing dye pigments is used for dye ink.

  The transport unit 20 includes two belt rollers 6 and 7 and an endless transport belt 8 wound around the rollers 6 and 7. The belt roller 7 is a driving roller, and rotates when a driving force is applied from a conveyance motor (not shown). The belt roller 6 is a driven roller and rotates as the conveyor belt 8 travels due to the rotation of the belt roller 7. A weakly adhesive silicon layer is formed on the outer peripheral surface of the conveyor belt 8 and holds the loaded paper P. The paper P placed on the outer peripheral surface of the transport belt 8 is transported to the left in FIG. A peeling plate 13 is disposed on the downstream side in the transport direction of the four inkjet heads 1. The paper P transported in the transport direction sequentially passes under the precoat head 2 and the four inkjet heads 1 and then is peeled off from the transport surface of the transport belt 8 by the peeling plate 13 and is also shown in the drawing of the transport belt 8. The paper is discharged to a paper discharge tray 14 arranged on the left side. The platen 10 is disposed to face the four inkjet heads 1 and the precoat head 2 and supports the upper loop of the conveyor belt 8 from the inside. Thereby, a predetermined gap suitable for image formation is formed between the outer peripheral surface of the conveyor belt 8 and the ejection surfaces of the four inkjet heads 1 and the precoat head 2.

  A rectangular ink discharge region 8 a occupying the entire width direction of the transport belt 8 and a precoat discharge region 8 b are formed at different positions in the circumferential direction of the transport belt 8. A liquid repellent treatment layer is formed on the surfaces of the ink discharge area 8a and the precoat discharge area 8b. In a maintenance operation described later, ink is discharged from the inkjet head 1 to the ink discharge area 8a, and precoat liquid is discharged from the precoat head 2 to the precoat discharge area 8b.

  The four inkjet heads 1 and the precoat head 2 have the same structure, each extend along the main scanning direction, and are arranged in parallel to each other in the sub scanning direction. The lower surface of each inkjet head 1 and precoat head 2 is an ejection surface in which a plurality of ejection ports 108 (see FIG. 3) are arranged. That is, the ink jet printer 101 is a line type color ink jet printer in which a plurality of ejection openings 108 for ejecting ink droplets in the main scanning direction are arranged.

  The outer peripheral surface of the upper loop of the conveyor belt 8 and each discharge surface are parallel to each other while facing each other. When the paper P conveyed by the conveyance belt 8 passes just below the precoat head 2, the precoat liquid is applied from the precoat head 2 so that the precoat liquid is applied to the area where the image is formed on the upper surface of the paper P. A droplet is ejected. Thereafter, when the paper P passes just below the four inkjet heads 1, ink droplets of each color are sequentially ejected from each inkjet head 1 to a region where the precoat liquid is applied on the upper surface of the paper P. Thereby, a desired color image is formed on the paper P. At this time, when the ink droplets land on the precoat liquid applied on the paper P, the precoat liquid aggregates or deposits the pigment component of the ink droplets, so that ink bleeding on the paper P is prevented and an image formed on the paper P The color developability is improved.

  Next, the inkjet head 1 and the precoat head 2 will be described in detail with reference to FIGS. Note that the precoat head 2 has the same structure as the ink jet head 1, and therefore the description thereof is omitted. In FIG. 3, for convenience of explanation, the pressure chamber 110, the aperture 112, and the discharge port 108 that are to be drawn with broken lines below the actuator unit 21 are drawn with solid lines.

  As shown in FIG. 2, the inkjet head 1 is a laminated body in which four actuator units 21 are fixed to the upper surface 9 a of the flow path unit 9. As shown in FIGS. 2 and 3, the flow path unit 9 has an ink flow path including a pressure chamber 110 and the like formed therein. The actuator unit 21 includes a plurality of actuators corresponding to the pressure chambers 110, and has a function of selectively giving ejection energy to the ink in the pressure chambers 110.

  The flow path unit 9 is a laminated body in which a plurality of metal plates made of stainless steel are aligned with each other. A large number of individual ink flow paths are formed in the flow path unit 9 from the manifold flow path 105 to the sub-manifold flow path 105a, and from the outlet of the sub-manifold flow path 105a to the discharge port 108 through the pressure chamber 110.

  A total of ten supply ports 105 b to which ink from a reservoir unit (not shown) is supplied are opened on the upper surface 9 a of the flow path unit 9. A discharge surface is formed on the lower surface of the flow path unit 9, and a large number of discharge ports 108 are arranged in a matrix. The ejection ports 108 are arranged at an interval of 600 dpi, which is the resolution in the main scanning direction with respect to the main scanning direction.

  The ink flow in the flow path unit 9 will be described. As shown in FIGS. 3 to 4, the ink supplied from the reservoir unit into the flow path unit 9 via the supply port 105b is distributed from the manifold flow path 105 to the sub-manifold flow path 105a. The ink in the sub-manifold channel 105 a flows into each individual ink channel and reaches the ejection port 108 via the pressure chamber 110.

  The ink pump 32 forcibly supplies ink to the supply port 105b of the flow path unit 9 via the reservoir unit so that the ink in the discharge port 108 is discharged to the outside in the corresponding inkjet head 1. Although one ink pump 32 is shown in FIG. 4, the inkjet printer 101 has four ink pumps 32 corresponding to each inkjet head 1.

  The precoat pump 33 forcibly supplies the precoat liquid to the supply port 105b of the flow path unit 9 through the reservoir unit so that the precoat liquid in the discharge port 108 is discharged to the outside in the precoat head 2.

  Returning to FIG. 1, the four inkjet heads 1 and the precoat head 2 are fixed to the frame 35. The head elevating mechanism 34 elevates and lowers the four inkjet heads 1 and the precoat head 2 together with the frame 35 in the vertical direction in FIG.

  The ink cleaner 37 cleans the ink discharge area 8a of the transport belt 8 from which ink has been discharged in a maintenance operation described later. The ink cleaner 37 includes a blade 37a, an ink collection unit 37b, and a waste ink tank 37c. The blade 37 a is a plate member made of an elastic material such as rubber, and is opposed to the entire width direction of the transport belt 8 at the lower left in FIG. 1 of the belt roller 7 on the downstream side in the transport direction of the four inkjet heads 1. It extends to. Further, the blade 37a is moved by a moving mechanism (not shown), the cleaning position (see FIGS. 1 and 5) where the tip abuts against the outer peripheral surface of the conveyor belt 8, and the retracted position (see FIG. 6) separated from the outer peripheral surface of the conveyor belt 8. Reference). When the transport belt 8 travels in the transport direction, the blade 37a disposed at the cleaning position when the ink discharge area 8a is curved from the top to the bottom at a position facing the belt roller 7 while moving in the transport direction. However, the ink on the ink discharge area 8a is wiped off. The ink collection unit 37b collects the ink wiped by the blade 37a and guides the collected ink to the waste ink tank 37c. The waste ink tank 37c stores the ink collected by the ink collection unit 37b.

  The precoat cleaner 38 cleans the precoat discharge area 8b of the transport belt 8 from which the precoat liquid has been discharged in a maintenance operation described later. The precoat cleaner 38 includes a blade 38a, a precoat liquid recovery unit 38b, and a waste precoat tank 38c. The blade 38a is a plate member made of an elastic material such as rubber, and is opposed to the entire width direction of the conveying belt 8 at the lower right in FIG. 1 of the belt roller 6 on the upstream side in the conveying direction of the precoat head 2. It is extended. The blade 38a is moved by a moving mechanism (not shown), the cleaning position (see FIG. 6) where the tip of the blade 38a contacts the outer peripheral surface of the conveyor belt 8, and the retracted position (see FIGS. 1 and 5) separated from the outer peripheral surface of the conveyor belt 8. Reference). When the transport belt 8 travels in the direction opposite to the transport direction, the precoat discharge area 8b moves in the direction opposite to the transport direction and curves from the upper side to the lower side at a position facing the belt roller 6. The blade 38a disposed in the position wipes off the precoat liquid on the precoat discharge area 8b. The precoat liquid collection unit 38b collects the precoat liquid wiped by the blade 38a and guides the collected precoat liquid to the waste precoat tank 38c. The waste precoat tank 38c stores the ink recovered by the precoat liquid recovery unit 38b.

Next, the control device 16 will be described with reference to FIG. The control device 16 includes a CPU (Central Processing Unit), a program executed by the CPU, and an EEPROM (Electrically Erasable and Programmable Read Only Memory) that stores data used for these programs in a rewritable manner. RA to memorize temporarily
M (Random Access Memory). Each functional unit constituting the control device 16 is constructed by cooperation of these hardware and software in the EEPROM. As shown in FIG. 4, the control device 16 controls the entire inkjet printer 101, and includes a conveyance control unit 50, an image data storage unit 41, a head control unit 42, a purge control unit 44, and a head lifting / lowering. A control unit 45 and a cleaner control unit 47 are provided.

  The conveyance control unit 50 controls the conveyance motor of the conveyance unit 20 so that the conveyance belt 8 travels at a desired speed and direction. The image data storage unit 41 stores image data relating to an image printed on the paper P.

  The head control unit 42 drives the actuator unit 21 of the precoat head 2 based on the image data stored in the image data storage unit 41 to discharge the precoat liquid droplets from the discharge port 108 at a desired timing. By driving the actuator unit 21 of each inkjet head 1, a desired volume of ink droplets is ejected from the ejection port 108 at a desired timing.

  The head lifting control unit 45 includes a printing position when the four inkjet heads 1 and the precoat head 2 perform printing on the paper P (see FIG. 1), an ejection surface of each inkjet head 1 and the precoat head 2, and a conveyance belt. The lifting / lowering operation of the frame 35 by the head lifting / lowering mechanism 34 is controlled so as to selectively take a maintenance position (see FIGS. 5 and 6) that is separated from the transport surface 8 by a predetermined distance. The maintenance position is located above the printing position (in the direction away from the conveyor belt 8).

  The purge control unit 44 controls the driving of the four ink pumps 32 so that the ink in the ejection ports 108 of the respective inkjet heads 1 is discharged into the ink discharge region 8a of the transport belt 8 in the maintenance operation. . Further, the purge control unit 44 controls the driving of the precoat pump 33 so that the precoat liquid in the discharge port 108 of the precoat head 2 is discharged to the precoat discharge region 8b of the transport belt 8 in the maintenance operation.

  In the maintenance operation, the cleaner control unit 47 allows the ink discharged by the purge control unit 44 to the ink discharge region 8a of the transport belt 8 to be wiped by the blade 37a of the ink cleaner 37, and the purge control unit 44. Thus, the travel of the transport belt 8 is controlled via the transport control unit 50 so that the precoat liquid discharged to the precoat discharge area 8b of the transport belt 8 is wiped by the blade 38a of the precoat cleaner 38, and the blade 37a, The position of 38a is controlled.

  Next, the maintenance operation of the ink jet printer 101 will be described. The maintenance operation is started immediately before the start of printing or by a command from the user. When the maintenance operation is started, as shown in FIG. 5A, the head lifting control unit 45 controls the head lifting mechanism 34 to move the four inkjet heads 1 and the precoat head 2 from the printing position to the maintenance position. Move. Further, the cleaner control unit 47 moves the blade 37a of the ink cleaner 37 to the cleaning position, moves the blade 38a of the precoat cleaner 38 to the retracted position, and causes the transport belt 8 to travel in the transport direction. As shown in FIGS. 5A and 5B, every time the ink discharge area 8a faces the black, cyan, magenta, and yellow ink jet heads 1 in order, the ink jet that faces the ink discharge area 8a. The purge controller 44 drives the ink pump 32 so that a predetermined amount of ink is discharged from each ejection port 108 of the head 1.

  Thereafter, as shown in FIG. 5C, the ink discharge area 8a reaches the position facing the blade 37a before facing the precoat head 2 and the blade 38a. At this time, the blade 37a disposed at the cleaning position wipes out the ink discharged to the ink discharge region 8a while the ink discharge region 8a is curved downward from above. Since the blade 38a is in the retracted position, it does not come into contact with the transport belt 8. The ink wiped by the blade 37a is collected in the ink collecting unit 37b and then stored in the waste ink tank 37c.

  When the blade 37a wipes all the ink discharged to the ink discharge area 8a, the cleaner control unit 47 places the blade 37a of the ink cleaner 37 in the retracted position and the blade 38a of the precoat cleaner 38 as shown in FIG. Are moved to the cleaning position, and the conveyor belt 8 is moved in the direction opposite to the conveying direction. Then, when the precoat discharge area 8 b faces the precoat head 2, the purge control unit 44 drives the precoat pump 33 so that a predetermined amount of precoat liquid is discharged from each discharge port 108 of the precoat head 2.

  Thereafter, as shown in FIG. 6B, the precoat discharge area 8b reaches a position facing the blade 38a before facing the four inkjet heads 1 and the blade 37a. At this time, the blade 38a disposed at the cleaning position wipes off the precoat liquid discharged to the precoat discharge region 8b while the precoat discharge region 8b is curved downward from above. Since the blade 37a is in the retracted position, it does not come into contact with the transport belt 8. The precoat liquid wiped by the blade 38a is collected in the precoat liquid collection unit 38b and then stored in the waste precoat tank 38c. When the blade 38a wipes all the precoat liquid in the precoat discharge area 8b, the head elevation controller 45 wipes the four inkjet heads 1 and the precoat head 2 after wiping the ejection surfaces of the heads 1 and 2 with a wiper (not shown). Move from the maintenance position to the printing position. This completes the maintenance operation.

  As described above, according to the inkjet printer 101 of the present embodiment, in the maintenance operation, the ink discharged to the ink discharge region 8a is wiped by the blade 37a without facing the blade 38a and discharged to the precoat discharge region 8b. The precoat liquid is wiped by the blade 38a without facing the blade 37a. For this reason, the ink discharged on the conveying surface of the conveying belt 8 and the precoat liquid do not mix with each other, and aggregates and precipitates of ink pigments are generated and fixed on the conveying surface, the ink cleaner 37 and the precoat cleaner 38. Can be suppressed. As a result, it is possible to prevent a decrease in the conveying ability of the paper P related to the conveying unit 20 and the cleaning ability of the ink cleaner 37 and the precoat cleaner 38.

  Further, in the maintenance operation, the ink discharged to the ink discharge area 8 a is wiped by the blade 37 a without facing the precoat head 2, and the precoat liquid discharged to the precoat discharge area 8 b faces the four inkjet heads 1. Therefore, the discharged ink is prevented from adhering to the ejection port 108 of the precoat head 2 and the discharged precoat liquid from adhering to the ejection port 108 of the inkjet head 1. be able to. As a result, it is possible to suppress the agglomeration or deposit of ink pigment from adhering to the ejection port 108. Further, since the ink cleaner 37 and the precoat cleaner 38 are disposed on both sides of the four inkjet heads 1 and the precoat head 2 in the transport direction, the inkjet head 1 and the precoat head 2 can be brought close to each other. In addition, the relative attachment accuracy of the precoat head 2 can be increased, and the ink jet printer 101 can be miniaturized.

  The ink discharged to the ink discharge area 8a is collected in the waste ink tank 37c after being collected in the ink collection section 37b, and the precoat liquid discharged to the precoat discharge area 8b is collected in the precoat liquid collection section 38b. After that, it is stored in the waste precoat tank 38c. As a result, the discharged ink and the precoat liquid are removed and stored without being mixed with each other, and agglomerates and precipitates of ink pigments can be prevented from sticking in the recovery path of the ink and the precoat liquid. .

  In addition, in a state where the ink discharge area 8a is curved from the upper side to the lower side, the blade 37a wipes the ink discharged to the ink discharge area 8a, so that the ink discharged to the ink discharge area 8a has risen. Since the ink is removed in a state, the ink discharged to the ink discharge region 8a can be efficiently removed. In addition, the blade 38a wipes off the precoat liquid discharged to the precoat discharge area 8b in a state where the precoat discharge area 8b is curved downward from above, so that the precoat liquid discharged to the precoat discharge area 8b rises. Therefore, the precoat liquid discharged to the precoat discharge area 8b can be efficiently removed.

  In addition, since the ink discharge area 8 a and the precoat discharge area 8 b are formed at different positions in the circumferential direction on the conveyance belt 8, ink pigment aggregates and precipitates are fixed on the conveyance surface of the conveyance belt 8. Can be further prevented.

Second Embodiment
An ink jet printer 201 according to a second embodiment of the present invention will be described. In addition, about the member substantially the same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted. As shown in FIG. 7A, the blade 37a is opposed to a planar region that is a part of the conveyance surface facing upward of the conveyance belt 8 on the downstream side in the conveyance direction of the four inkjet heads 1. The blade 38a is opposed to the planar region on the upstream side in the transport direction of the precoat head 2.

  In the maintenance operation, the cleaner control unit 47 moves the blade 37a of the ink cleaner 37 to the cleaning position, moves the blade 38a of the precoat cleaner 38 to the retracted position, and causes the transport belt 8 to travel in the transport direction. Each time the ink discharge area 8a faces the black, cyan, magenta, and yellow ink jet heads 1 in order, a predetermined amount of ink is discharged from each ejection port 108 of the ink jet head 1 facing the ink discharge area 8a. As described above, the purge control unit 44 drives the ink pump 32. Thereafter, before the ink discharge area 8a faces the precoat head 2 and the blade 38a, the ink discharge area 8a reaches a position facing the blade 37a, and the ink discharged to the ink discharge area 8a reaches the blade 37a arranged at the cleaning position. Wiped out.

  Further, as shown in FIG. 7B, the cleaner control unit 47 moves the blade 37a of the ink cleaner 37 to the retracted position, moves the blade 38a of the precoat cleaner 38 to the cleaning position, and moves the conveying belt 8 in the conveying direction. Drive in the opposite direction. Then, when the precoat discharge area 8 b faces the precoat head 2, the purge control unit 44 drives the precoat pump 33 so that a predetermined amount of precoat liquid is discharged from each discharge port 108 of the precoat head 2. Thereafter, before the precoat discharge area 8b faces the four inkjet heads 1 and the blade 37a, the precoat discharge area 8b reaches a position facing the blade 38a, and the precoat liquid discharged to the precoat discharge area 8b is arranged at the cleaning position. It is wiped by the blade 38a.

  According to the inkjet printer 201 of the second embodiment, in the maintenance operation, the ink discharged to the ink discharge area 8a is wiped by the blade 37a without facing the precoat head 2 and the blade 38a and discharged to the precoat discharge area 8b. Since the precoat liquid is wiped by the blade 38a without facing the four inkjet heads 1 and the blade 37a, the ink discharged to the transport surface of the transport belt 8 and the precoat liquid do not mix with each other, It is possible to suppress the occurrence of ink pigment aggregates and precipitates on the transport surface. Further, since the ink discharge area 8a and the precoat discharge area 8b do not pass below the precoat head 2 and the four inkjet heads 1, respectively, the discharged ink adheres to the discharge port 108 of the precoat head 2 or is discharged. It is possible to prevent the precoat liquid from adhering to the ejection port 108 of the inkjet head 1.

  Furthermore, since the discharged ink and precoat liquid are wiped by the blades 37a and 38b in the plane area of the transport belt 8, it is possible to suppress the discharged ink and precoat liquid from leaking from the transport surface.

<Third Embodiment>
An ink jet printer 301 according to a third embodiment of the present invention will be described. In addition, about the member substantially the same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted. As shown in FIG. 8A, the blade 37 a faces a planar region that is a part of the outer peripheral surface facing upward of the conveying belt 8 on the downstream side in the conveying direction of the four inkjet heads 1. The blade 38a faces the planar region on the upstream side in the transport direction of the four inkjet heads 1 and on the downstream side in the transport direction of the precoat head 2.

  In the maintenance operation, the cleaner control unit 47 moves the blade 37a of the ink cleaner 37 to the cleaning position, moves the blade 38a of the precoat cleaner 38 to the retracted position, and causes the transport belt 8 to travel in the transport direction. Each time the ink discharge area 8a faces the black, cyan, magenta, and yellow ink jet heads 1 in order, a predetermined amount of ink is discharged from each ejection port 108 of the ink jet head 1 facing the ink discharge area 8a. As described above, the purge control unit 44 drives the ink pump 32. Thereafter, before the ink discharge area 8a faces the precoat head 2 and the blade 38a, the ink discharge area 8a reaches a position facing the blade 37a, and the ink discharged to the ink discharge area 8a reaches the blade 37a arranged at the cleaning position. Wiped out.

  Further, as shown in FIG. 8B, the cleaner controller 47 cleans the blade 38a of the precoat cleaner 38 with the blade 37a of the ink cleaner 37 in the retracted position with the conveyor belt 8 traveling in the conveyance direction. Move to each position. Then, when the precoat discharge area 8b faces the precoat head 2, the purge control unit 44 precoats so that a predetermined amount of precoat liquid is discharged from each discharge port 108 of the precoat head 2 facing the precoat discharge area 8b. The pump 33 is driven. Thereafter, before the precoat discharge area 8b faces the four inkjet heads 1 and the blade 37a, the precoat discharge area 8b reaches a position facing the blade 38a, and the precoat liquid discharged to the precoat discharge area 8b is arranged at the cleaning position. It is wiped by the blade 38a.

  According to the inkjet printer 201 of the third embodiment, in the maintenance operation, the ink discharged to the ink discharge area 8a is wiped by the blade 37a without facing the precoat head 2 and the blade 38a, and discharged to the precoat discharge area 8b. Since the precoat liquid is wiped by the blade 38a without facing the four inkjet heads 1 and the blade 37a, the ink discharged to the transport surface of the transport belt 8 and the precoat liquid do not mix with each other, It is possible to suppress the occurrence of ink pigment aggregates and precipitates on the transport surface. Further, since the ink discharge area 8a and the precoat discharge area 8b do not pass below the precoat head 2 and the four inkjet heads 1, respectively, the discharged ink adheres to the discharge port 108 of the precoat head 2 or is discharged. It is possible to prevent the precoat liquid from adhering to the ejection port 108 of the inkjet head 1.

  Further, when the ink discharged to the ink discharge area 8a is wiped and when the precoat liquid discharged to the precoat discharge area 8b is wiped, it is not necessary to switch the traveling direction of the conveyor belt 8, and thus the discharged ink is discharged. The maintenance operation can be completed quickly by wiping the ink and the precoat liquid in a continuous operation.

<Fourth embodiment>
An ink jet printer 401 according to a fourth embodiment of the present invention will be described. In addition, about the member substantially the same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted. As shown in FIG. 9, the ink jet printer 401 has a cleaner 439. The cleaner 439 includes a blade 439a, an ink recovery unit 437b, and a precoat liquid recovery unit 438b. The blade 439a is arranged on the upstream side of the four inkjet heads 1 and the downstream side of the precoat head 2 with respect to the transport direction, and is opposed to a planar region that is a part of the outer peripheral surface facing upward of the transport belt 8. doing. Further, the blade 439a is tilted by about 10 degrees with respect to the direction orthogonal to the transport direction (the left end in FIG. 9 is located downstream of the right end in the transport direction), and the width direction of the transport belt 8 It extends beyond both ends. The downstream surface in the transport direction of the blade 439a is an ink wiping surface 437a, and the upstream surface in the transport direction is a precoat liquid wiping surface 438a. The blade 439 a can selectively take a maintenance position where the tip of the blade 439 a comes into contact with the conveyor belt 8 and a retracted position separated from the conveyor belt 8.

  The ink recovery unit 437b is opposed to the upstream end (the right end in FIG. 9) in the conveyance direction of the blade 439a. The precoat liquid recovery unit 438b faces the downstream end (left end in FIG. 9) in the conveyance direction of the blade 439a.

  In the maintenance operation, the blade 439a is moved to the maintenance position and the conveyor belt 8 is run in the direction opposite to the conveyor direction, and ink is discharged from the four inkjet heads 1 onto the conveyor surface of the conveyor belt 8. The discharged ink moves in the direction opposite to the transport direction as the transport belt 8 travels, and is wiped onto the ink wiping surface 437a of the blade 439a before facing the precoat head 2 and the precoat liquid wiping surface 438a of the blade 439a. Is done. The ink wiped on the ink wiping surface 437a moves to the right in FIG. 9 along the ink wiping surface 437a, and falls downward from the right end portion of the blade 439a. The dropped ink is collected in the ink collecting unit 437b and stored in the waste ink tank 37c.

  Thereafter, the transport belt 8 is caused to travel in the transport direction, and the precoat liquid is discharged from the precoat head 2 onto the transport surface of the transport belt 8. The discharged precoat liquid moves in the transport direction as the transport belt 8 travels and wipes the precoat liquid wiping surface 438a of the blade 439a before facing the ink wiping surfaces 437a of the four inkjet heads 1 and the blade 439a. Is done. The precoat liquid wiped onto the precoat liquid wiping surface 438a moves to the left in FIG. 9 along the precoat liquid wiping surface 438a and falls downward from the left end of the blade 439a. The dropped ink is collected in the precoat liquid collecting unit 438b and stored in the waste precoat tank 38c.

  According to the inkjet printer 201 of the fourth embodiment, in the maintenance operation, the ink discharged to the transport belt 8 is wiped to the ink wiping surface 437a without facing the precoat head 2 and the precoat liquid wiping surface 438a, and the transport belt 8 Since the precoat liquid discharged to the front surface is wiped to the precoat liquid wiping surface 438a without facing the four inkjet heads 1 and the ink wiping surface 437a, the ink and precoat liquid discharged to the transport surface of the transport belt 8 Are not mixed with each other, and it is possible to suppress the occurrence of aggregates and precipitates of ink pigments on the transport surface. Further, since the discharged ink and the discharged precoat liquid do not pass below the precoat head 2 and the four inkjet heads 1, respectively, the discharged ink adheres to the discharge port 108 of the precoat head 2 or is discharged. It is possible to prevent the precoat liquid from adhering to the ejection port 108 of the inkjet head 1.

  Furthermore, since the single blade 439a wipes out the discharged ink and precoat liquid, the ink jet printer 401 can be downsized.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. In the first embodiment described above, the blades 37a and 38a are configured to wipe the discharged ink and precoat liquid on the curved surface in which the conveyance surface of the conveyance belt 8 curves downward from above. In the third embodiment, the blades 37a and 38a are configured to wipe the discharged ink and precoat liquid in the plane region of the conveyor belt 8, but either one of the blades 37a and 38a is discharged on the curved surface. The other liquid may be wiped away, and the other may wipe away the liquid discharged in the plane area.

  In the first to fourth embodiments described above, the discharged ink and the precoat liquid are stored in the waste ink tank 37c and the waste precoat tank 38c through different paths, respectively. The ink and the precoat liquid may be stored in the same tank through the same or different paths.

  Further, in the first to third embodiments described above, the ink is discharged to the ink discharge area 8a and the precoat liquid is discharged to the precoat discharge area 8b. However, the ink and the precoat liquid are formed on the conveyance belt. The same area may be discharged, or the ink or the precoat liquid may be discharged to an arbitrary position related to the conveying surface of the conveying belt.

  In addition, in the above-described first to fourth embodiments, the precoat head 2 is arranged on the upstream side in the transport direction of the four inkjet heads 1, but the treatment liquid that aggregates or deposits the ink pigment is used. The ejecting head may be disposed on the downstream side in the transport direction of the four inkjet heads 1.

  In the first to fourth embodiments described above, the four inkjet heads 1 are configured to eject ink droplets of different colors. However, two, three, or five or more inkjet heads 1 have different color ink droplets. May be configured such that one ink jet head ejects ink droplets and precoat droplets of a plurality of colors.

  The present invention is also applicable to a liquid ejecting apparatus that ejects liquid other than ink. Further, the present invention is not limited to a printer, and can be applied to a facsimile, a copier, and the like.

DESCRIPTION OF SYMBOLS 1 Inkjet head 2 Precoat head 6, 7 Belt roller 8 Conveyor belt 8a Ink discharge area 8b Precoat discharge area 16 Control device 20 Conveyance unit 32 Ink pump 33 Precoat pump 37 Ink cleaner 37a Blade 37b, 437b Ink recovery part 37c Waste ink tank 38 Precoat cleaner 38a Blade 38b, 438b Precoat liquid recovery unit 38c Waste precoat tank 42 Head control unit 44 Purge control unit 47 Cleaner control unit 50 Transport control unit 101, 201, 301, 401 Inkjet printer 108 Discharge port 437a Ink wiping surface 438a Precoat liquid Wiping surface 439 Cleaner 439a Blade

Claims (5)

A transport mechanism for transporting a recording medium by moving an endless transport surface;
A first liquid head having a first discharge port for discharging a first liquid for forming an image on a recording medium;
A second discharge port for discharging a second liquid that is provided at a position different from the first liquid head with respect to the conveyance direction of the recording medium and acts on the first liquid to aggregate or deposit components in the first liquid. A second liquid head formed with:
First discharge means for discharging the first liquid from the first discharge port;
Second discharge means for discharging the second liquid from the second discharge port;
A first cleaning mechanism having a first removal member that removes the first liquid adhering to the transport surface by contacting the transport surface;
A second cleaning mechanism having a second removal member that removes the second liquid adhering to the transport surface by contacting the transport surface;
Control means for controlling the transport mechanism, the first and second discharge means, and the first and second cleaning mechanisms,
The first liquid head is disposed downstream of the second liquid head in the transport direction;
The first removal member is disposed downstream of the first liquid head in the transport direction;
The second removal member is disposed between the first liquid head and the second liquid head in the transport direction;
The control unit controls the transport mechanism and the first discharge unit to discharge the first liquid onto the transport surface, and then discharges the first liquid from the first discharge port to the transport surface. The transport mechanism and the first cleaning mechanism are such that the first liquid adhering to the surface is removed by the first removal member without reaching the position facing the second removal member and the second discharge port. controls, then, the second liquid after controlling the second discharge means to the conveying mechanism so as to discharge onto the transport surface, wherein by being discharged to the conveying surface from the second discharge port The transport mechanism and the second cleaning are performed such that the second liquid attached to the transport surface is removed by the second removal member without reaching the position facing the first removal member and the first discharge port. It is characterized by controlling the mechanism A liquid ejection apparatus. The first cleaning mechanism further includes a first storage mechanism for storing the first liquid removed by the first removal member,
The second cleaning mechanism further includes a second storage mechanism for storing the second liquid removed by the second removal member,
A flow path for guiding the first liquid removed by the first removal member to the first storage mechanism, and a flow path for guiding the second liquid removed by the second removal member to the second storage mechanism. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting apparatuses are different from each other. Claim 1 wherein at least one of the first and second removing member, characterized in that the removal of the first or the second liquid adhering to the conveyance surface in a planar region facing upwardly in the conveying surface Or the liquid discharge apparatus of 2. 3. The liquid ejection according to claim 1, wherein the first removal member removes the first liquid adhering to the transport surface on a curved surface that curves downward from above on the transport surface. apparatus. The control means discharges the liquid from the first discharge port to the first discharge area on the transfer surface, and sets the second discharge area to be different from the first discharge area with respect to the transfer direction on the transfer surface. as the liquid from the second discharge port is discharged, the conveying mechanism, the liquid according to any one of claims 1 to 4, wherein the controller controls the first discharge means and the second discharge means Discharge device.

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